In the area of door sealings, hose connections and low water zones of mechanical dishwashers, that is, where the surfaces of the interior of the dishwasher are not exposed to the direct and intensive operating pressure spray of the cleaning liquor, soil is frequently deposited in the course of time. This soil consists mainly of finely-divided fatty food residues.
Occasional unavoidable troubles in the ionexchange system of the dishwasher water supply, which serve to soften the water used, or the consistent underdosing of the dishwasher detergents by the user also cause increasingly deposits of a mixture of calcium from hard water and residues of the detergents on the inner surfaces of the machines.
Partly so-called "tempering colors" are formed, as rainbow-colored discolorations of refined steel parts of the dishwasher are called.
These deposits represent an undesired nutrient soil for rotting processes, which manifest themselves by an unpleasant odor, particularly when the dishwasher is opened after it has not been used for a long time. Beyond that, hose connections and sealing materials, particularly at the door, are damaged by prolonged action of these soil deposits.
The commercial powdered alkaline dishwasher detergents or acid clear rinse agents are not suitable for cleaning the so-called "problem zones" of dishwashers where soil is particularly likely to be deposited. These dishwasher detergents are dosed into the washing and rinsing cycle of the dishwashers and are dissolved therein; however, the soiled regions either are not touched at all or only too briefly by them. So, soil is depositing in the interior of the dishwashers in spite of the use of these detergents. It is, therefore, necessary to clean these special zones manually. The detergents used for cleaning the dishes are unsuitable for this purpose, since they irritate the skin. Commercial cleansers for hard surfaces are not suitable either for these special applications, since they contain generally high-sudsing tensides or surface-active compounds whose residues can lead to various troubles in dishwashers.